Ask HN: Is there a easy connector between MongoDB and Postgres?

I have a postgres schema for relating authors, posts, comments, likes, follows, and all kinds of stuff that works great for relational queries.

The articles table in particular is great, with the exception of the "body" column, where all the sudden I'm hosting a large markdown file.

I want to have an "article_bodies" table in MongoDB that holds many [article_id:article_body] entries, which in my understanding is what MongoDB was made for. I'm thinking this will open higher performance from my postgres, while allowing me to keep writing relational queries everywhere.

Is there a fast and easy way to connect my pg "articles" table to a mongo "articles" table? I'm using PostgREST to host the rest API, will this have the performance impact I'm expecting?

I'm a self-taught webdev, but it seems like more or less everything is either best served by a relational db or a document db, with mongo and postgres being the most widely used standards. Are there any projects/companies dedicated to supporting tooling that links these two? Could we finally be done building new databases?